Modelling and identification of magnetorheological vehicle suspension

Abstract

The paper presents methods of estimation of vehicle suspension system parameters based on kinetic measurements. The vehicle suspension is assumed to include springs, linear dampers and magnetorheological (MR) dampers which are known to be nonlinear. In many cases hysteresis loop is revealed in the static characteristics of MR dampers. Nonlinear full-car vehicle suspension model is defined and adapted for using linear and nonlinear leastsquares identification method. Identifications experiments are performed assuming limited number of available kinetic sensors. Solution space with respect to the location of the vehicle body's gravity center is presented as well as quality index values and time diagrams are reported based on estimated model parameters and simulation results. nonlinear vehicle suspension system; full-car model; magnetorheological damper; least-squares method

FxLMS algorithm with preview for vibration control of a half-car model with magnetorheological dampers

“…A full-car model [14], [15] which exhibits 7 DOFs (degrees of freedom) maps vertical motion and rotation of the vehicle body mass (heave, pitch and roll of the sprung mass) and vertical motion of the vehicle wheels (unsprung masses). The experimental vehicle can be assumed with high accuracy as symmetrical with respect to the longitudinal cross-section.…”

Fuzzy Control for Semi-Active Vehicle Suspension

“…A significant amount of papers use 2 degree of freedom (2 DoF) quarter models [1,4,9]. Recently, a 7 DoF model, also referred to as the 'full-car model', has become popular [3,5,7,12,15]. There are also publications that use different car models [10].…”

Comparison of Control Strategies in a Semi-Active Suspension System of the Experimental ATV

“…Parameters of linearized model are listed in Table 1. The inverse model was derived based on (7) and formed as follows: (9) The inverse model (9) gives a required control voltage v mr needed to supply the MR damper in order to make the damper generate a desired force F mr .…”

“…Such additional information can be used in simulation for validation of a control algorithm as well as included in the control scheme to improve its performance. Well-known full-car models [7,8] which exhibit 7 degrees of freedom (7 DOFs) describe vehicle as 3-dimentional frame supported by four wheels. In case of full-car model vertical dynamics of four wheels as well as heave, pitch and roll dynamics of vehicle body are mapped.…”

“…Sprung mass (vehicle body) and unsprung masses (wheels) are connected using linear springs, passive dampers and additional nonlinear elements which describe parameters of vehicle suspension and vehicle tyres. Some road applications require the full-car vehicle model to be limited to a half-car 4 DOFs model [9]; the method can be justified in case of longitudinally symmetrical construction of vehicles or symmetrical road-induced kinematic excitation. Moreover, limitation of full-car model simplifies analysis of vehicle dynamics.…”